Guide to Field Sobriety Tests in SC

Can I be Arrested for Failing an FST?

Field sobriety tests (FSTs) were created to help law enforcement gauge the relative sobriety or intoxication of a driver, and cannot be used to determine blood alcohol level. However, a police officer who has pulled a suspicious motorist or who is working a sobriety checkpoint can request a battery of field sobriety tests in determining probable cause of an arrest and the use of an evidentiary alcohol test.

If you’ve been arrested and charged with a DUI based on your performance during a field sobriety test that led to the accumulation of additional evidence against you, contact us for a no-cost, immediate case consultation (call or use the form on this page). During our initial consultation, we’ll help you to determine if you should plead guilty or not guilty to your charge. Learn more about our DUI defense.

The Right to Refuse an FST
The motorist has the right to refuse participation in roadside sobriety tests. Declining to take a roadside test does not carry the same consequences as refusing to take a breathalyzer, though the motorist may be arrested on suspicion of DUI for refusing an FST. That is the police officer’s discretion.

What Happens in Roadside Sobriety Test?

  • Field sobriety tests, like other aspects of a DUI arrest, must be videotaped. Law enforcement is tasked with providing evidence of driving impairment in the conviction of a DUI. The videotape serves as a witness for both parties. NOTE: In the event of an accident where EMTs arrive first, an officer may not be able to properly videotape the scene, in which case, human witnesses will be used to corroborate testimony for either party.
  • The driver will be asked to perform a battery of field sobriety tests. One test alone cannot accurately indicate sobriety or intoxication. Based on decades of studies, the National Highway Traffic Safety Administration has determined three standardized field sobriety tests administered sequentially, yield the most accurate results — when officers are properly trained. These are the Horizontal Gaze Nystagmus (HGN), Walk-and-Turn (WAT), and One-Leg Stand (OLS). (Scroll down for video demonstrations.) The cumulative test results are more accurate than each individual test. But the NHTSA has not been able to produce completely accurate results.
  • The driver may be asked to blow into a handheld breathalyzer/ breath alcohol test. A handheld device is classified as a field sobriety test and may be used for a preliminary BAC measurement. Refusal of a handheld device, which is not evidentiary in court, should be treated the same as refusing any other FST.

If you’re arrested for your performance during a field sobriety test, your DUI lawyer at Strom Law Firm can review strategies to challenge the validity of FSTs. For more see, Challenging DUI Testing.

Common FSTs Defined

Horizontal gaze nystagmus test:

The officer passes a pen or similar object in front of your face and you are asked to follow it with your eyes. This tests your body’s physiological response which the NHSTA believes can highlight intoxication in motorists who have become adept at performing motor skills while under the influence. Con: Supposedly, if your eyes jerk or tremble (nystagmus) when the pen is passed from side to side, it indicates intoxication. However, the officer should admit that nystagmus can, and does, occur naturally in many people, and that stress and bright lights (which are present at every traffic stop) can bring an onset of nystagmus.

Walk the line/walk and turn test:

The police officer will ask you to keep your hands at your side, walk heel-to-toe 12 steps (counting each aloud), turn and walk back.

They will be looking for “clues,” such as you are unbalanced during instructions, you stopped while walking, your heel and toe didn’t touch, you used your arms for balance, you made an improper turn (often a “pirouette,” like a ballet dancer) and you made an incorrect number of steps.

This test asks you to make a very unnatural movement that few sober people can do. There are many challenges to this test: the slope of the road, presence of gravel, heavy clothing in the winter, high heels, passing traffic dangers, distracting squad lights as well as officer spotlights.

Stand on one leg:

Only pelicans are physically qualified to do this test. The rest of the bipedal creatures have a great deal of difficulty, unless they are gymnasts or police officers who practice it every night by the roadside while arresting fellow citizens. They will ask you to put your feet together and then raise one foot and count up to 30 using “one thousand one,” etc. They will record any swaying, using arms for balance, hopping and putting your foot down. The same test conditions that are troubling for the walk-and-turn, apply here.

ABC or number testing: you are asked to recite the alphabet or a series of numbers whether forward or backward. This is not a recognized test, should not be part of any probable cause analysis, and can be challenged on that ground alone. The police will ask you to state the alphabet without singing it. It sounds simple but invariably people miss a letter, get rattled, begin again, etc.

Finger to nose test: while standing still with your eyes closed, you are asked to move your index finger to your nose.

Rhomberg balance test: you are asked to stand still, close your eyes, tilt your head up and approximate 30 seconds. The officer is looking for your sense of time, along with whether you can stand still or sway from side to side.

Contact a DUI Lawyer

Arrested for driving under the influence? Criminal defense lawyers at the Strom Law Firm, LLC provide a no-fee consultation to discuss the facts of your DUI case and to discuss whether to plead guilty or not guilty. Call us today at 803-252-4800 to review your case.


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  3. […] you have been pulled over on suspicion of DUI and you participated in a field sobriety test which resulted in SC DUI charges, we are here to help. Conveniently located in Columbia, SC, the Strom Law DUI attorneys offer a […]

  4. […] you are pulled over for a suspected DUI, you may be subjected to a field sobriety test or a Breathalyzer test. These tests must be videotaped by the police officer, and the officer […]

  5. […] officer who has pulled a suspicious motorist or who is working a sobriety checkpoint can request a battery of field sobriety tests which will likely then provide the officer with probable cause for an arrest and the use of […]

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